Electrochemically driven, cobalt-carbon bond-mediated direct intramolecular cyclic and acyclic perfluoroalkylation of (hetero)arenes using X(CF 2 ) 4 X.

A proof-of-concept for the one-step, synthetically challenging cyclic and acyclic perfluoroalkylation of (hetero)arenes driven by the valence change of a vitamin B 12 derivative as a cobalt catalyst in the presence of fluoroalkylating reagents (X(CF 2 ) 4 X) is presented. The consecutive formation of cobalt-carbon bonds and generation of fluoroalkyl radicals by homolysis are the key steps for the reaction to proceed.